Sup Jets. The first one : It's too simple. You should make more effects. Second : I like the pixelated parts. But I don't like the sparkles. Third and fourth : Nothing so special about them. The effects are somehow boring (?)
7/10. Put more effort and I know you'll be able to make better sigs.
Looks pretty good for being new at the time you created them, there very simple without brush spam, as I like it. I don't really like the text to be honest, doesn't really fit in the sigs. But that's some nice work, also a 7/10 from me.
Life is like Basketball. Aim, Concentrate, Balance and Following through. That's all you ever need to accomplish your goals.